Color photographic elements

ABSTRACT

NONDIFFUSIBLE HYDROXYLATED TRINUCLEAR STABILIZER COMPOUNDS INCLUDING THE 2,2 - (B-ISOPROPYL)-TETRAMETHYLENE6-CHROMANOLS, THE 2-2-(B,B-DIMETHYL)-PENTAMETHYLENE-6CHROMANOLS AND THE 5A,6,7,8,9,9A - HEXAHYDRO-2-DIBENZOFURANOLS ARE ADVANTAGEOUSLY INCORPORATED IN HYDROPHILIC COLLOID LAYERS OF PHOTOGRAPHIC ELEMENTS IN WHICH COLOR PHOTOGRAPHIC DYE IMAGES ARE TO BE STORED FOR VIEWING. THE STABILIZER COMPOUNDS PROTECT DYE IMAGES AGAINST THE FADING EFFECTS OF PROLONGED EXPOSURE TO LIGHT.

United States Patent 3,574,627 COLQR PHOTOGRAPHIC ELEMENTS Max H. Sternand Gregory J. Lestina, Rochester, N.Y., assignors to Eastman KodakCompany, Rochester, N.Y. No Drawing. Filed Feb. 6, 1969, Ser. No.797,276 Int. Cl. G03c 1/90, 7/00 US. Cl. 96-100 20 Clalms ABSTRACT OFTHE DISCLOSURE Nondiffusible hydroxylated trinuclear stabilizercompounds including the 2,2 (fit-isopropyl)-tetramethylene-6-chromanols, the 2,2-([3,;3-dimethyl)-pentamethylene-6- chromanols andthe 5a,6,7,8,9,9a hexahydro-Z-dibenzofuranols are advantageouslyincorporated in hydrophilic colloid layers of photographic elements inwhich color photographic dye images are to be stored for viewing. Thestabilizer compounds protect dye images against the fading effects ofprolonged exposure to light.

This invention relates to photography, photographic materials includingcolor photographic materials containing dye image stabilizing agents,and methods for improving the stabilities of dyes in photographicmaterials.

The formation of dye images by the chromogenic development of silverhalide photographic materials, involving the coupling reaction ofoxidized primary aromatic amino developing agents with couplingcompounds to form indophenol, indamine, azomethine, phenoxazine,phenazine, and similar dyes, is well known. In this system, thesubtractive color process of color formation is ordinarily used and theimage dyes customarily formed are cyan, magenta, and yellow, which arethe colors that are complementary to the primary colors, red, green andblue, respectively. Usually phenolic couplers (i.e., phenols andnaphthols) are used to form the cyan dye image; pyrazolone orcyanoacetyl couplers are used to form the magenta dye image; andacylacetamide or dibenzoylmethane couplers are used to form the yellowdye image.

In these color photographic systems, the color-forming coupler may beapplied in a developer solution or incorporated in the light-sensitivephotographic emulsion layer or in another dye-image-forming layer, sothat, during development, it is available to react with oxidized colordeveloping agent formed as the result of latent image development.

The dye images formed in such processes are not indefinitely stable toultraviolet radiation so that under rigorous viewing or displayconditions involving, for example, long periods of exposure to sunlight,or other ultraviolet radiant illumination, the dyes may fade, resultingin deterioration in the quality of the picture.

Increases in the stability of indophenol, indoaniline, and azomethinedyes to ultraviolet radiation have been achieved by the use of a varietyof agents which can be added to the emulsion in processing, or moreconveniently, in manufacture. Lestina and Reckhow describe the use ofdinuclear 6-hydroxy chroman stabilizers in photographic elements in US.Ser. No. 452,889, filed May 3, 1965, now Pat. No. 3,432,300. The needremains for still other stabilizers that will further enhance theresistance of these dyes to actinic light.

It is therefore an object of our invention to provide novel photographicelements containing dyes and/ or dyeforming compounds, and hydroxylatedtricyclic stabilizer compounds to increase the stability of the dyesagainst ultraviolet and visible light radiation.

Another object of our invention is to provide novel image dyestabilizing agents which do not form highly colored oxidation productsin the processing baths, e.g., bleach baths, etc., used in colorphotographic processing.

Another object of our invention is to provide novel color photographicimage-forming layers comprising hydrophilic colloid film-forming binderscontaining finely particulate dispersions of solutions of ourhydroxylated trinuclear stabilizing agents.

It is a further object to provide such layers also containing couplers.

A further object is to provide novel dispersions of our hydroxylatedtrinuclear stabilizing agents which can be incorporated in silver halideemulsion layers without adverse emulsion effects.

It is a still further object of our invention to provide processed colorphotographic layers containing dye images in association with thehydroxylated trinuclear stabilizing agents of our invention.

These and other objects will be apparent from a consideration of thefollowing specification and claims.

These and still other objects are accomplished according to ourinvention by addition to layers intended for the storage of colorphotographic dye images, of dye stabilizing quantities of anondiffusible hydroxylated trinuclear stabilizer compound including a2,2 (fr-isopropyl)-tetramethylene 6 chromanol, a 2,2-(B,B-dimethyl)-pentamethylene-6-chromanol, and a 5a,6,7,8,9,9ahexahydro-Z-dibenzofuranol.

Particularly advantageous dye-stabilizing agents for the practice of ourinvention are included in the nondiffusible hydroxylated trinuclearstabilizers having the formulas:

I Be

wherein R and R each represents hydrogen, a lower alkyl group,preferably alkyl of 1 to 4 carbon atoms (e.g., methyl, ethyl, propyl,isopropyl, butyl, t-butyl, etc.) or a lower alkoxy group preferablyhaving from 1 to 4 carbon atoms (e.g., methoxy, ethoxy, butoxy,t-butoxy, etc.); R represents hydrogen, an alkyl group preferably analkyl group having from 1 to 18 carbon atoms including an acyclic alkylgroup having from 1 to 18 carbon atoms, e.g., methyl, butyl, octadecyl,t-butyl, t-octyl, isopropyl, cyclopentylmethyl, 2 cyclopentylethyl, 4cyclopentylbutyl, cyclopentyloctadecyl, 2cyclopentyl-1,1-dirnethylethyl, cyclohexylmethyl, 2-cyclohexylethyl,3-cyclohexylpropyl, 4 cyclohexylbutyl, w-cyclohexyloctadecyl, etc., acyclic alkyl group, e.g., a cycloalkyl group, such as, a cyclopentylgroup (e.g., cyclopentyl, l-methylcyclopentyl, l-ethylcyclopentyl, 1propylcyclopentyl, 1-butylcyclopentyl, etc.), a cyclohexyl group (e.g.,cyclohexyl group, l-methylcyclohexyl, 1 ethylcyclohexyl,l-propylcyclohexyl, l-butylcyclohexyl, etc.) or an alkoxy group in whichthe alkyl moiety is any of the alkyl groups defined for R, such thatwhen R is hydrogen R is preferably a branched chain lower alkyl group; Rand R are hydrogen and isopropyl such that when R is hydrogen, R isisopropyl and when R is hydrogen, R is isopropyl. Typical illustrativecompounds are listed below.

Compound No. Name 22r(ti-isopropyl)-tetramethylene-7-t-octyl-6'chromanol.

III

wherein R R and R are as defined previously, R R R and R each representhydrogen, methyl, isopropyl, lower hydroxyalkyl having from 1 to 3carbon atoms (e.g., hydroxymethyl, Z-hydroxyethyl, 3-hydroxypropyl,etc.), carboxyalkyl having from 2 to 4 carbon atoms (e.g.,carboxymethyl, '2 carboxyethyl, 3 carboxypropyl, etc.), and alkoxyalkylhaving from 2 to 4 carbon atoms (e.g., propoxymethyl, ethoxyethyl,methoxypropyl, etc.), such that when R is hydrogen, R is hydrogen, and Rand R are methyl isopropyl, hydroxyalkyl, carboxyalkyl and alkoxyalkylsuch that one of R and R is isopropyl, and such that when R, ishydrogen, R is hydrogen and R and R are methyl, isopropyl, hydroxyalkyl,carboxyalkyl, alkoxyalkyl such that one of R and R is isopropyl.

Typical examples of stabilizers of Formula III include the following:

(a) 5 a,6,7,8,9,9a-hexahydro-5 a-isopropyl-8-methyl-3-toctyl)-2-dibenzofuranol (b) 5a,6,7,8,9,9a-hexahydro-5a-methyl-8-isopropyl-3-(tbutyl -2-dibenzofuranol (c) 5a,6,7,8,9,9a-hexahydro-7-isopropyl-9a-methyl-3- (tbutyl)-'2-dibenzofuranol (d)5a,6,7,8,9,9a-hexahydro-7-methyl-9a-isopropy1-3-(tbutyl-2-dibenzofuranol (e) 5a,6,7,8,9,9a-hexahydro-5a- 2-hydroxyethyl) -8-isopropyl-3-(t-butyl -2-dibenzofuranol (f) 5a,-6,7,8,9,9a-hexahydro-7-isopropyl-9a-( 2-hydroxyethyl) -3- (t-butyl)-2-dibenzofuranol (g) 5a,6,7,8,9,9a-hexahydro-Sa-isopropyl-8-carboxymethyl-3-(t-buty1)-2-dibenzofurano1(h) 5a,6,7,8,9,9a-hexahydro-Sa-methyl-8-isopropyl-3- (toctyl)-2'dibenzofuranol.

The 1-, d-optical isomers of our stabilizers as well as various mixturesof these are equally effective as .stabilizing agents according to ourinvention.

Our stabilizing agents are advantageously used to improve the stabilityof the indophenol, indoaniline and azomethine dyes, such as, thoseproduced by chromogenic development, the azo dyes produced in well-knowndiazotype elements, and dyes produced in well-known silverdye-bleachelements and the dyes used in dye transfer, dye imbibition and dyediffusion transfer systems. Our stabilizing agents are advantageouslyincorporated in the layer in which the dye image will be stored afterimage formation; this is either the layer in 'which a nondiffusible dyeimage is formed or the layer to which a diffusible dye image istransferred, such as, the image-receiving layer of a receiving sheet ina dye-transfer system, a dyeimbibition system or a dye-diffusiontransfer system. The

2,2-(fl-isopropyl)-tetramethylene-7-t-butyl-tlchromanol.

..... 2,2-(fl,fl-dimethyl)-pentamethylene-7-is0propyl-6-chromanol.

2,2- (B,fl-dlmethyl)-pentamethylene-7-t-butyl-dchromanol.2,2-09,B-dimethylg-pentamethylene-7-t-butyl-B-methyl-(ichromanol.

-pentamethylene-7-cyclohexyl-Gchromanol.

2,2-(fi,fl-dimethyl)-pentamethylene-7-cyelopentyl-(S-ehromanol.

2,2-(5,,8-dlmethyl)-pentamethylene-7-(l-methylcyclopentyl)-6-chromanol.

2,2(B,fl-dimethyl)-pentamethylene-7-cyclohexylmethyl-6-chromanol.

2,2-(BJS-dlmethyD-pentamethylene7-n-octyl-6-chromanol.

2,2(fi,fl-dl1nethyl)-pentamethylenefl-boctyl-6-chromanol.

specific method used to form the indophenol, indoaniline, azomethine, orazo dye is not important since any of the well-known image-formingelements and processes are used advantageously.

Our stabilizers are particularly efiicacious in protecting dyes producedby chromogenic development of any of the well-known 5-pyrazolonecouplers used in photography for magenta dye formation. Typical magentadyes are those produced by color development of couplers described inU.S. patents, such as 2,600,788, 2,725,292, 2,908,573, 3,006,759,3,062,653, 3,152,896, 3,311,476 and Young U.S. application Ser. No.458,455, filed May 24, 1965, which couplers are herein incorporated byreference.

Cyan dye-forming couplers of such U.S. patents as 2,474,293, 2,725,292,2,895,826, 2,908,573 produce cyan dyes upon chromogenic development thatare advantageously stabilized against light exposure by our stabilizingcompounds.

Yellow dye-forming couplers of U.S. Pat. 2,908,573 produce yellow dyesthat are made less subject to the fading effects of prolonged exposureto light by the presence of our stabilizing compounds.

Our stabilizing agents are incorporated alone or together with acolor-forming coupler in a dye image-forming layer of a colorphotographic element. A useful method of dispersing our stabilizingcompounds is that described for dispersing couplers in Mannes et al.U.S. Pat. 2,304,939, issued Dec. 15, 1942; Jelley et al. U.S. Pat.2,322,027, issued June 15, 1943, etc., in which highboiling organicsolvents are used to dissolve the material. Other applicable methods aredescribed in Vittum et al. U.S. Pat. 2,801,170, and Fierke et al. U.S.Pat. 2,801,171, both issued July 30, 1957, and Julian U.S. Pat.2,949,360. issued Aug. 16, 1960, in which low-boiling or water-solubleorganic solvents are used with high-boiling solvent.

In these methods of dispersion our stabilizing agents can be containedin the same dispersion with nondifiusing couplers, or in a separatedispersion, and the couplers can optionally be dispersed directly in theemulsion. Highboiling solvents useful is dispersing the hydroxylated tricyclic stabilizer compounds of our invention include di-nbutylphthalate,benzylphthalate, triphenyl phosphate, trio-cresyl phosphate, diphenylmono-p-tert-butylphenyl phosphate, monophenyl di-p-tert-butylphenylphosphate, diphenyl mono-o-chlorophenyl phosphate, monophenyldio-chlorophenyl phosphate, tri-p-tert-butylphenyl mono- (S-tert-butyl 2phenylphenyl)phosphate, 2,4-di-n-amylphenol, 2,4-di-t-amylphenol,N,N-diethylaurarnide, etc.

The low-boiling or water-soluble organic solvents which can be used toadvantage with the high-boiling solvents are disclosed in patents, suchas Fierke et al., U.S. Pat. 2,801,171, and Vittum et al., U.S. Pat.2,801,170, both issued July 30, 1957, and Julian U.S. Pat. 2,949,360,issued Aug. 16, 1960, etc.

The organic solvents include:

1) Low-boiling, substantially Water-insoluble organic solvents, such as,methyl, ethyl, propyl, and butyl acetates, isopropyl acetate, ethylpropionate, sec-butyl alcohol, ethyl formate, butyl formate,nitromethane, nitroethane, carbon tetrachloride, chloroform, etc., and

(2) Water-soluble organic solvents, such as methyl isobutyl ketone,B-ethoxyethyl acetate, tetrahydrofurfuryl adipate, Carbitol acetate(diethyleneglycol monoacetate), methoxytriglycol acetate, methylCellosolve acetate, acetonyl acetone, diacetone alcohol, butyl Carbitol,butyl Cellosolve, methyl Carbitol, methyl Cellosolve, ethylene gycol,diethylene gycol, dipropylene glyco, acetone, methanol, ethanol,acetonitrile, dimethylformamide, dioxane, etc.

Combinations of two or more of the new and improved dye-stabilizingagents of our invention may be used. These agents may also be used incombination with other addenda in the same dispersion, for example,other stabilizing agents, antistain agents, e.g., ballastedhydroquinones, phenolic antioxidants, etc. The selection of the specificstabilizer compound and the concentration used in each layer of amultilayer film can be varied over a wide range, and will depend on theimprovement in resistance to fading required for each of the image dyesin the respective layers.

Any of the well-known primary aromatic amino colorforming silver halidedeveloping agents such as the phenylenediamines, e.-g.,N,N-diethyl-p-phenylenediamine hydrochloride, N-monomethyl pphenylenediarnine hydrochloride, N,N-dimethyl-p-phenylenediaminehydrochloride, 2-amino-5-diethylaminotoluene hydrochloride,2-amino-5-(N-ethyl-N-laurylamino)toluene, N-ethyl-N-fl-(methylsulfonamido)ethyl 3 methyl-4-aminoaniline sulfate,N-ethyl-N-(B-methylsulfonamidoethyl) 4 aminoaniline, 4-(N-ethyl-N-s-hydroxyethyl)aminoaniline, etc., the p-aminophenols and theirsubstitution products where the amino group is unsubstituted, e.g.,2,6-dichloro-4- aminophenol, 2-bromo-p-aminophenol,2,6-diiodo-4-aminophenol, 4-aminophenol, etc., may be used to developphotographic coatings containing our stabilizers. Various othermaterials may be included in the developer solutions depending upon theparticular requirements, for example, image-forming couplers, competingcouplers, antifoggants, hardeners, an alkali metal sulfite, bisulfite,alkaline buffer salts, bromide, iodide, etc., and the thickening agentsused in viscous developer compositions. A typical developer solution isgiven in Example 2, but does not limit the invention.

Our stabilizers are incorporated in hydrophilic colloid layers intendedfor the storage of photographic dye images, such as, a receiving sheetfor receiving a difiusible transferred dye image or a dye-image forminglayer containing a light-sensitive material such as silver halide (e.g.,silver chloride, silver bromide, silver iodide, silver chlorobromide,silver chlorobromoiodide, silver bromoiodide, etc.), a light-sensitivediazo compound (as in diazo-type material), etc.

Hydrophilic colloids used to advantage in the image layers include anyof the hydrophilic colloids used in image-forming layers and inreceiving layers, such as gelatin, and gelatin derivatives, casein andother proteinaceous colloids, hydrophilic cellulosic derivatives, e.g.carboxymethyl cellulose, alginates, synthetic resins, e.g., polyvinylalcohol, copoly(ethylacrylate, acrylic acid) polyvinyl pyrrolidone, etc.Some colloids used to advantage are polyvinyl alcohol or a hydrolyzedpolyvinyl acetate as described in US. Pat. 2,286,215, a far hydrolyzedcellulose ester, such as cellulose acetate hydrolyzed to an acetylcontent of 19-26%, as described in US. Pat. 2,327,808, a water-solubleethanolamine cellulose acetate as described in U.S. Pat. 2,322,085, apolyacrylamide having a combined acrylamide content of 30-60% and aspecific viscosity of 025- on an imidized polyacrylamide of likeacrylarnide content and viscosity as de scribed in US. Pat. 2,541,474,zein as described in US. Pat. 2,563,791, a vinyl alcohol polymercontaining urethane carboxylic acid groups of the type described in US.Pat. 2,768,154, or containing cyano-acetyl groups, such as the vinylalcohol-vinyl cyano-acetate copolyrner as described in US. Pat.2,808,331, or a polymeric material which results from polymerizing aprotein or a saturated acylated protein with a monomer having a vinylgroup as described in US. Pat. 2,852,382.

The emulsions used in the photographic element of our invention can bechemically or optically sensitized.

Our stabilizing compounds are also used to advantage with mordants indye-image receiving sheets for dye diffusion transfer processes such asare described in French Pat. 75,676, dlivr June 19, 1961. Mordantreceiving sheets in which our compounds can be used to advantage aredescribed in French Patent 1,361,293, dlivr Apr. 6, 1964. When thediffusible-image dyes are mordanted in such receiving sheets containingour stabilizer compounds, they exhibit marked improvement in lightstability.

Usually emulsions containing our stabilizer compounds are coated onphotographic supports in the form of multilayer color photographicelements wherein at least three differently sensitized emulsion layersare coated over one another on the support. Usually the support iscoated in succession with a red-sensitive layer, a green-sensitivelayer, and a blue-sensitive layer either with or Without a Carey Leafilter layer between the blue-sensitive and green-sensitive layers. Thethree differently color sensitized layers may be arranged in any otherorder over one another that is desirable; however, the Carey Lea filterlayer (i.e., yellow colloidal silver) would not be put over theblue-sensitive layer. Preferably, these light-sensitive layers arearranged on the same side of the support.

In general, our stabilizing agents are used in quantities ranging from0.25 mole to 20 moles of stabilizer per 1 mole of coupler used (or per 1mole of dye produced). The preferred range is from 1 mole to 5 moles ofstabilizer per mole of coupler (or per mole of dye produced). Thefollowing examples are included for a further understanding of ourinvention.

EXAMPLE 1 Four single layer gelatinous coatings containing a preformedmagenta dye are made on cellulose acetate film support. The coatingshave the following compositions:

TABLE I Tricresyl phosphatemg./ft.

Stabilizer indicated in Table II-10- mole/ft. Gelatin-733 trng./ft.

Tri-isopropylnaphthalene sulfonate33 mg./ft. Saponin-25 mg./ft.

The magenta dye is prepared by reacting the coupler, 1 (2 chloro 4, 6dimethylphenyl) 3 {3 [a (3- pentadecylphenoxy)butyramido1benzamido} 5pyrazolone (described as coupler No. 6 in US. Pat. 3,062,653), dissolvedin tricresyl phosphate with the oxidized form of color-developing agent,N ethyl B methanesulfonamidoethyl 3 methyl 4 aminoaniline sulfate. Thefour coatings are subjected to a light fading test for three weeks SANS(i.e., 500 ft. candles simulated average north sky light from a filteredxenon arc). The stabilizer and the loss in magenta dye density (from anarea of the dye image having an original magenta dye density pfblabout1.2) data are summarized in the following The results show that ourstabilizer compounds N0. 2 and b produce about an 86% improvement in thestability of the preformed magenta dye in coatings Nos. 3 and 4 comparedto coating No. l (the control) when subjected to the 3 weeks SANS test.Prior art compound 7 X is 2,2 dimethyl 4 isopropyl 6 hydroxy 7-t-octylchroman of French Pat. 1,478,141, dlivr Mar. 13, 1967.

Similar results are obtained when Example 1 is repeated using magentadyes produced from the magenta 8 EXAMPLE 3 Example 2. is repeated usingmagenta dye-forming -pyrazolone couplers 1 through 12 of US. Pat.2,600,788 in place of the coupler used in Example 2. The results arecoupler and the oxidized form of other Well-known color 5 slmllar tothose obtamed m Examp 1e developing agents including those disclosedherein previ- EXAMPLE 4 ously. Similar results are obtained when Example1 1s Example 2 is repeated using magenta d f i repeafied 115mg any Q thewell'known magenta S-pyrazolone couplers 6 through 9' of US. Pat.2,908,573 formmg couplers Wlth OXldlZed form any of w 10 in place of thecoupler used in Example 2. The results wrell knoltglin color-developmgagents described herem are Similar to those obtained in Example ev1ous pEXAMPLE 2 EXAMPLE 5 Three single layer gelatinous silver halide emulsionExjample 2 is repeated using colored magenta coatings containing themagenta dye-forming coupler, g% f fi 7 a E 1 (2 chloro 4,6dimethylphenyl) 3 {3 [0c (3- a m P ace 0 e coup er usepentadecylphenoxy)butyramido]benzatmido} 5 pyr amgle 2. 1In thisexamglie the dye oflthe 00111113161 remamcilng olone are made on a papersupport. The gelatinous e C0 or Processe ayer as as magenta Ye silverhalide emulsion is prepared as described by Trivelli formed by Pouplerthat colfpled Wlth X1d1Z ed color and Smith in The Photographic Journal,page 330, May 20 veloper during color processing are both stabilizedagainst 1939. The coatings have the following compositions: rg g effectsof Prolonged exposure to light in e a 111g test. TABLE III Similarly thevaluable stabilizing effect of our stabiliz- C0upler (identifiedabove)-5O mg./ft, mg agents can be demonstrated for still other dyespar- Tricresyl 50 /ft 2 ticularly the dyes formed by chromogenicdevelopment of Stabilizer (as indicated in Table 'IV)-equimolar to y ofThe known -PY couplerscoupler EXAMPLE 6 Gelatin-440 mg./ft.Tri-isopropylnaphthalene sulfonate-20 m-g./ft. Example 2 1s rapeaffiidusmg our Stablhzer Compound 9 nag/ft; in place of our stabilizercompound 2 and using the 3 weeks SANS test. The results are summarizedin Table V The coatings are dried and given /2 second exposure on below;a 1B intensity scale sensitometer, followed by color TABLE v processingat 75 as follows:

mi... tates: C0101- development 6 Coating No. Stabilizer density 105sStop-fix 3 g ----&N: Wash 2 omp un 0.9 .48 Ferricyanide bleach 4 Wash 340 in this example our compound No. 9 produces a 53% Hardening fix "d 3improvement 1n the stability of the magenta dye image W ash 8 upon theprolonged exposure to light. Bufier (stabilizer) 1 3 EXAMPLE 7 The colordeveloper is a conventional color developer Example 2 is repeated usingstabilizer compounds (a) solution containing benzyl alcohol, sodiumsulfite, the and (b) in place of stabilizer compound No. 2. The recolordeveloping agent, N ethyl [3 methanesulfonsults are summarized below:atmidoethyl 3 methyl 4 arninoaniline sulfate and an alkali to give a pHof about 10. A conventional stop-fix 1 week SANS 3weeks SANS bathcontaining sodium th osulfate, sodium sulfite, acetlc Coating Stabilizerii g gffigg; i acid, bor1c acid and potassium alum is used for thestopfix p and for the hardening fix t p in the process 5331331311333:finltaata'tiij 3% 3'21 A conventional alkali metal ferricyanide-bromidebleach 3 Compound b-1111: 0114 0:43 bath is used, and a conventionalaqueous citric acid stabilizer bath having a pH of 3.5 is used in theprocess. The EXAMPLE 3 magenta dye density is measured in each processedcoat- Example 2 is repeated usin g stabilizer compound h in mg beforeand 1 W SANS and 3 Weeks SANS place of stabilizer compound No. 2. Theresults are sumfading test as described in Example 1. The results aremarized below: summarized in the following table.

1 week SAdNS 3 Weeks SANS TABLE IV Coating No. Stabilizer iiiiisit? 10 ti e n s iig iii;

lweek SANS 3weeks SANS 1 None 0 62 0 92 t d d Coating No. Stabilizeritiiriit? 10%? 132% 2 Cmpmndh 14 1 N t 1 0.5 2.. P33?.o;2.20undX 0.113.21 65 P E 9 3 Compound No. 2 (of 0.08 0.24

invention). A gelatinous silver halide emulsion is prepared as describedby Trivelli and Smith in The Photographic Journal, page 330, May 1939.One portion of this emulsion The results show that our stabilizer No. 2produces an is coa ed as a control identified as coating No. 1 on a 86%improvement in the stability of the magenta dye cellulose acetate filmsupport. Coating No. 2 is made of images formed by color development incoating No. 3 another portion of the emulsion to which our stabilizingcompared to coating No. 1 (the control) when subjected Compound No. 2 isadded so that it is coated at a rate to the 1 week SANS test and aimprovement in the of 10 mole (of stabilizer) per ft. Coating No. 3 isstability of the magenta dye when subjected to the 3 made of anotherportion of the emulsion to which our weeks SANS test. 75 stabilizingcompound N0. 9 is added so that it is coated at the same rate asstabilizing compound No. 2. The coatings are given a sensitometricexposure and color developed in a conventional magenta color developingsolution containing the color developing agent, 4-amino-N-ethyl-N-(fl-methanesulfonamidoethyl)m-toluidine sesquisulfate monohydrate, analkali, an alkali metal sulfite and the magenta dye-formin g coupler,1-(2,4,6-trichlorophenyl) -3- (2,4-dichloroanilino)-5-pyrazolone(coupler No. 6 of US. Pat. 3,152,896). The color developed coatings arethen water washed, bleached in a conventional alkali metalferricyanide-bromide bleach, fixed in a conventional alkali metalthiosulfate fixing bath washed and dried. Our stabilizer compounds 2 and9 in coatings 2 and 3 impart valuable protection to the magenta dyeimages as is illus trated by 1 and 3 weeks SANS tests as described inExample 2.

Similar results are obtained when Example 9 is repeated with otherdye-stabilizing compounds of our invention and with other primaryaromatic amine color developing agents and other magenta dye-formingcouplers including couplers l, 2, 3, 4, 5, 7 and 8 of US. Pat. 3,152,896as well as other diifusible magenta dyeforming couplers well known inthe art.

Our stabilizer compounds are advantageously incorporated in thereceiving layer of image receiving sheets to stabilize the dye imagestransferred thereto. For example, image transfer dyes made fromcompounds I through XLVI of US. Pat, 3,227,551 and transferred toreceiving layers containing our stabilizer compounds have improvedstability to prolonged exposure to light. Similarly, dye images producedfrom dye developers such as those described in US. Pat. 3,404,002 andtransferred to receiving layers containing our stabilizer compounds arefound to fade less upon prolonged exposure to light than the same imagestransferred to a receiving layer containing none of our stabilizers.

Similarly, the azo dye images produced in silver dyebleach elementscontaining our stabilizers are substantially more stable to prolongedexposure to light than images that are not so protected. Thus ourstabilizers are advantageously incorporated in silver dye-bleachmaterials, such as those described in US. Pats. 2,418,624, 2,420,630,2,420,631, etc.

Our stabilizing compounds are also advantageously incorporated in theazo dye image-forming layer of any of the diazo-type elements that areused for duplicating images. Thus our stabilizer compound isincorporated into the polymeric matrix layer containing the diazosalt(s) and coupler(s) where it advantageously protects the azo dyeimage produced upon development of the light image exposed layer.

In general, the stabilizer compounds of our invention are prepared byreacting a compound of the formula:

wherein R R and R are as defined previously, with a C terpene in thepresence of an acid catalyst such as zinc chloride, boron trifluorideetherate, etc., in an appropriate solvent, for example, a halogenatedhydrocarbon (e.g., chloroform, dichloroethane, carbontetrachloride,etc.) preferably at a temperature in the range from about to 20 C.

Compounds of Formulas I and II are advantageously prepared by reacting acompound of Formula IV with V. CH3 CH oHi Ct...

Compound 2, for example, is advantageously made by heatingt-butylhydroquinone with myrcene in acetic acid with zinc chloridecatalyst at '50 to 60 C. for about 4 hours. Compound No. 2 as acrystalline product is obtained having a M.P. of l45l47 C.

Compound No. 9 is advantageously made by the method described forcompound No. 2 but using an equimolar amount of t-octylhydroquinone inplace of tbutylhydroquinone. Compound No. 9' as a crystalline product isobtained having a M.P. of 15ll53 C.

Compounds 1, 3, 4, 5, 6, 7, 8, l0 and 11 are advantageously prepared bythe methods indicated above for compound No. 2 excepting that thet-butylhydroquinone is replaced by the appropriate hydroquinonederivative as indicated in the following table:

Compound No.: Compound of Formula IV used 1 Isopropylhydroquinone.

3 2-t-butyl-3-methylhydroquinone. 4 Cyclohexylhydroquinone.

5 Cyclopentylhydroquinone.

6 l-methylcyclopentylhydroquinone. 7 Cyclohexylmethyl.

8 n-Octylhydroquinone.

10 n-Decylhydroquinone.

11 Octadecylhydroquinone.

Compound No. 12 is isolated from the reaction mixture used to makecompound No. 1. Compound No. 13 is isolated from the reaction mixtureused to make compound No. 2 and compound No. 14 is isolated from thereaction mixture used to make compound No. 9.

The 5a,6,7,8,9,9a-hexahydro-2-dibenzofuranols of Formula III areadvantageously prepared by reacting the appropriate compound of FormulaIV with an acyclic C terpene, such as, linalool in acetic acidcontaining a catalyst such as zinc chloride preferably under reflux.Substantially higher yields of compounds of Formula III areadvantageously obtained by reacting the appropriate compound of FormulaIV with the appropriate C cyclic terpene or derivative thereof, such as,limonene, a-pinene, u-phellandrene, etc., at a temperature of from about5 to about 20 C. with an acid catalyst, such as, borontrifluoride-etherate preferably in a halogenated hydrocarbon-ethersolvent mixture, e.g., a mixture of diethyl ether with1,2-dichloroethane or chloroform or carbontetrachloride.

Compound a is produced by condensation of t-octylhydroquinone andlinalool in refluxing acetic acid containing zinc chloride. The purifiedproduct has a melting point of C.

In a preferred synthesis the compounds of Formula III are advantageouslyprepared in good yields by treating solutions of the appropriatehydroquinone of Formula IV and the appropriate cyclic terpene in a 4:2:1mixture of chloroform, carbontetrachloride and ether cooled to 5- 10 C.with boron trifluoride etherate and storing at 5 to 20 C. until thecondensation is completed usually from about 2 to 10 days. The productsare then isolated by appropriate methods such as chromatography afterwashing the organic layer with dilute (1 N) sodium hydroxide and withWater to neutrality.

Compounds a and h are advantageously prepared by condensingt-octylhydroquinone with d-limonene using the procedure described above.

Compounds b, c and d are advantageously prepared by this method in whicht-butylhydroquinone is condensed 11 with d-limonene. These compounds areisolated in different fractions using chromatography.

Compounds e and f are prepared by treating a solution of 0.1 mole ofNopol (trade name for 6,6-dimethylbicyclo-[3,1,l]-hept-2-ene 2 ethanol)and 0.1 mole of t-butylhydroquinone in 175 ml. of 6:1 chloroform-etherwith 4 ml. of, boron trifiuoride-etherate at 20 C. for 10 days. Thecrude product is purified by molecular distillation, followed byrecrystallation from acetonitrile to give a crystalline product with amelting point of l90l92 C.

Compound g is advantageously prepared by condenshept-Z-ene-Z-acetic acidin chloroform-carbontetrachloride hept-2-ene-2-acetic acid in chloroformcarbontetrachloride-ether containing boron trifiuoride-etherate held at5 at 20 C.

Our hydrophilic colloid layers containing dye images, such as,indophenol dye images, indoaniline dye images, azomethine dye images andazo dye images and a stabilizing amount of a nondiifusible hydroxylatedtricyclic stabilizer compound, such as, a2,2-(B-isopropyl)-tetramethylene-G-chromanol, and a2,2-(j3,fl-dimethyl)pentamethylene-G-chromanol provide a valuabletechnical advance in color image reproduction because these images aresubstantially more stable than the same images in layers containing nostabilizer or a prior art stabilizer.

The invention has been described in detail with particular reference tocertain preferred embodiments thereof, but it will be understood thatvariations and modifications can be eifected within the spirit and scopeof the invention.

We claim:

1. A hydrophilic colloid layer containing a color photographic dyeimage, said layer containing at least one nonditfusible, hydroxylatedtricyclic stabilizer compound for said dye, said stabilizer compoundbeing selected from the class consisting of a2,2-(fi-isopropyl)-tetramethylene- 6-chromanol, a 2,2 (5,5dimethyl)-pentamethylene-6- chromanol, and a 5a,6,7,8,9,9a-hexahydro 2benzofuranol.

2. A hydrophilic colloid layer containing a color photographic dyeimage, said layer containing at least one nondififusible hydroxylatedtricyclic stabilizer compound selected from the class consisting ofthose having the formulas:

| I HO HO and R- R3 CQCHs 1 12 wherein R represents a member selectedfrom the class consisting of hydrogen, an alkyl group and an alkoxygroup: R and R each represents a member selected from the classconsisting of hydrogen, a lower alkyl group and a lower alkoxy group;and R and R each represent a member selected from the classs consistingof hydrogen and isopropyl, such that when R is hydrogen, R is isopropyland when R is hydrogen, R is isopropyl.

3. A hydrophilic colloid layer containing a color photographic dyeimage, said layer containing at least one nondiflusible hydroxylatedtricyclic stabilizer compound selected from the class consisting ofthose having the formula:

consisting of hydrogen, an alkyl group, and an alkoxy group; R and Reach represents a. member selected from the class consisting ofhydrogen, a lower alkyl group and a lower alkoxy group; R R R and R eachrepresent a member selected from the class consisting of hydrogen,methyl, lower hydroxyalkyl having from 1 to 3 carbon atoms, carboxyalkylhaving from 2 to 4 carbon atoms and alkoxyalkyl having from 2 to 5carbon atoms, such that when R is hydrogen, R is hydrogen, and R and Rare methyl, isopropyl, hydroxyalkyl, carboxyalkyl and alkoxyalkyl suchthat one of R and R is isopropyl, and such that when R; is hydrogen, Ris hydrogen and R and R are methyl, isopropyl, hydroxyalkyl,carboxyalkyl, alkoxyalkyl such that one of R and R is isopropyl.

4. A dye image-forming silver halide emulsion layer comprising afilm-forming hydrophilic colloid containing at least one nondifiusiblehydroxylated tricyclic stabilizer compound for stabilizing said dyeimage against the ef fects of prolonged exposure to light, said compoundbeing selected from the class consisting of a 2,2-(B-isopropyl)-tetramethylene-6-chromanol, a2,2-(6,,8-dimethyl)-pentamethylene-6-chromanol and a5a,6,7,8,9,9a-hexahydro-2- benzofuranol.

5. A dye image-forming silver halide emulsion layer comprising afilm-forming hydrophilic colloid containing at least one nondifiusiblehydroxylated tricyclic stabilizer compound for stabilizing said dyeimage against the effects of prolonged exposure to light, said compoundbeing selected from the class consisting of those having the formulas:

Ru l) R- O and R- 0 Rs I ti I M ---R2 CH3 CH3 wherein R represents amember selected from the class consisting of hydrogen, an alkyl groupand an alkoxy group; R and R each represents a member selected from theclass consisting of hydrogen, a lower alkyl group and a lower alkoxygroup; and R and R each represent a member selected from the classconsisting of hydrogen and isopropyl, such that when R is hydrogen, R isisopropyl and when R is hydrogen, R is isopropyl.

6. A dye image-forming silver halide emulsion layer comprising afilm-forming hydrophilic colloid containing at least one nondifiusinghydroxylated tricycle stabilizer compound for stabilizing said dye imageagainst the effects of prolonged exposure to light, said compound beingselected from the class consisting of those having the formula:

wherein R represents a member selected from the class consisting ofhydrogen, an alkyl group, and an alkoxy group; R and R each represents amember selected from the class consisting of hydrogen, a lower alkylgroup and a lower alkoxy group; R R R and R each represent a memberselected from the class consisting of hydrogen, methyl, lowerhydroxyalkyl having from 1 to 3 carbon atoms, carboxyalkyl having from 2to 4 carbon atoms and alkoxy-alkyl having from 2 to 4 carbon atoms, suchthat when R is hydrogen, R is hydrogen, and R and R are methyl,isopropyl, hydroxyalkyl, carboxyalkyl and alkoxyalkyl such that one of Rand R is isopropyl, and such 13 that when R is hydrogen, R is hydrogenand R and R are methyl, isopropyl, hydroxyalkyl, carboxyalkyl,alkoxyalkyl such that one of R and R is isopropyl.

7. A dye image-forming silver halide emulsion layer of claim 4containing an incorporated magenta dye-forming coupler.

8. A dye image-forming silver halide emulsion layer of claim 4 in whichthe hydrophilic colloid is gelatin.

9. A dye-image-forming silver halide emulsion layer comprising afilm-forming hydrophilic colloid containing at least one nondiflusiblehydroxylated tricyclic stabilizer compound for stabilizing said dyeimage against the eifects of prolonged exposure to light, said compoundbeing selected from the class having the formula:

wherein R represents an alkyl group; and [R and R represents a memberselected from the class consisting of hydrogen and a straight chainlower alkyl group.

10. A dye image-forming silver halide emulsion layer of claim 9 in whichR in the structural formula of the stabilizer compound representst-butyl.

11. A dye image-forming silver halide emulsion layer of claim 9 in whichR in the structural formula of the stabilizer compound representst-octyl.

12. A dye image-forming silver halide emulsion layer comprising afilm-forming hydrophilic colloid containing at least one nonditfusiblehydroxylated tricyclic stabilizer compound for stabilizing said dyeimage against the effects of prolonged exposure to light, said compoundbeing selected from the class having the formula:

wherein R represents an alkyl group; R and R each represents a memberselected from the class consisting of hydrogen and a straight chainlower alkyl group; and R and R each represent a member selected from theclass consisting of hydrogen and isopropyl, such that when R ishydrogen, R is isopropyl, and when R is hydrogen, R is isopropyl.

13. A light-sensitive gelatino silver halide emulsion layer containing2,2- (5,}8-dimethyl) pentamethylene-7-t-butyl- 6-chromanol.

14. A light-sensitive gelatino silver halide emulsion layer containing2,2- (,8,fi-dimethyl)pentamethylene-7-t-octyl-6-chromanol.

15. A light-sensitive gelatino silver halide emulsion layer containing2,2 (fl-ispropyl)-tetramethy1ene-7-t-butyl-6-chromanol.

16. A light-sensitive gelatino silver halide emulsion layer containing5a,6,7,8,9,9a-hexahydro 5a isopropyl-S-methyl'3-(t-octyl)-2-dibenzofuranol.

17. A light-sensitive gelatino silver halide emulsion layer containing5a,6,7,8,9,9a hexahydro-5a-methyl-8-isopropyl-3 (t-butyl) -2-dibenzofuranol.

18. A light-sensitive gelatino silver halide emulsion layer containing5a,6,7,8,9,9a-hexahydro-5a-methyl-8-isopropyl- 3- (t-octyl-2-dibenzofuranol.

19. In an element for color photography designed for dye image storage,said element comprising a support layer and at least one hydrophiliccolloid layer for said dye image, the improvement comprising the use ofa hydrophilic colloid layer containing a dye stabilizing amount of anondilr'usible dye stabilizer selected from the class consisting of a2,2-(fi-isopropyl)-tetramethylene-6-chro manol, a2,2-(fi,{3-dimethyl)pentamethylene-6-chromanol, and a5a,6,7,8,9,9a-hexahydro-Z-benzofuranol.

20. In an element for color photography designed for dye image storage,said element comprising a support layer and at least one hydrophiliccolloid layer for said dye image, the improvement comprising the use ofa hydro- 7 philic colloid layer containing a dye stabilizing amount of anonditfusible dye stabilizer selected from those having the formula:

IO: R1

References Cited UNITED STATES PATENTS 2,461,484 2/1949 Thompson 96-843,016,306 .1/1962 Mader et al. 96--84 2,461,485 2/ 1949 Thompson 96843,432,300 3/.1969 Lestina et al 96-56 NORMAN G. TORCHIN, PrimaryExaminer E. C. KIMLIN, Assistant Examiner US. Cl. X.lR. 96'91 52 3UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 57h,627 Dated April 1 3, 1 971 lnventofl Max H. Stern and Gregory J. LestinaIt is certified that error appears in the above-identified patent andthat said Letters Patent are hereby corrected as shown below:

. l Column 11 line L .5 second formula should read Column 11 line 59"classs" should read "class";

Column 12, line 51 "tricycle" should read "tricyolic" and Signed andealed this 19th day of October 1 971 (SEAL) Atteat .J EDWARDM.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Acting Commissionerof Patents

